JP2012095601A - Agricultural film and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyethylene agricultural film which can increase the harvest of field crops and increase nutrients by containing a specific light quality converting agent, and can stably retain an excellent light quality converting capability for a long period of time without generation of bubbles in the film; and to provide a method for producing the same.SOLUTION: The agricultural film includes at least one layer of a resin composition layer containing 0.01-5 pts.wt. of the light quality converting agent (D) relative to 100 pts.wt. of polyethylene resin (X). The MFR (the melt flow rate measured under the load of 21.18N at 190°C) of the whole polyethylene resin (X) constituting the agricultural film is 1.0-10 g/10 min, and the light quality converting agent (D) is a substance of a condensed product.

Description

  The present invention relates to an agricultural film, particularly an agricultural polyolefin resin film having a light quality conversion ability, and more specifically, containing a specific light quality conversion agent may increase crop yield and nutrients. It is possible to provide a polyethylene-based agricultural film that can be produced and that bubbles are not generated in the film and that good light quality conversion ability is stably maintained for a long period of time, and a method for producing the same.

  Focusing on the fact that the amount and nature of light are related to the promotion and suppression of crop growth, and applying light quality conversion technology that converts the wavelength distribution and intensity of light to agricultural films, Attempts have been made to make use of the plant for improving diseases, controlling pests, and controlling the growth of bacteria.

  For example, techniques for converting short wavelength light into a long wavelength using a fluorescent agent (Patent Document 1: Japanese Patent Publication No. 46-24376, Patent Document 2: Japanese Patent Laid-Open No. 50-88147) have been known for a long time. . In addition, a method of converting visible light into long wavelength light to enhance photosynthesis (Patent Document 3: Japanese Patent Laid-Open No. 6-41524), or a method of converting light having a wavelength in the ultraviolet region into long wavelength light. (Patent Document 4: JP-A-6-46684, Patent Document 5: JP-A-6-46685, Patent Document 6: JP-A-6-36685).

  Recently, there has also been proposed a polyolefin-based agricultural film in which a low-density polyethylene produced with a metallocene catalyst is blended with a light quality conversion agent of a specific cyanopyrazine derivative (Patent Document 7: JP-A-9-249775). Publication).

  However, these conventionally known light quality conversion agents are generally weak against heat, and when exposed to high temperatures, fading and reduction in conversion efficiency occur, so that it is difficult to maintain the light quality conversion ability over a long period of time. In addition, since there are various types of light quality conversion agents, it is difficult to select a light quality conversion agent that performs light quality conversion that is truly useful for agricultural crops. Therefore, practical films having good and stable light quality conversion ability and performance of other agricultural films are hardly obtained in agricultural films that are used for several years after being deployed in agricultural houses. That is the situation.

Conventionally, vinyl chloride resin films have been widely used as agricultural films, but polyolefin resin films that do not have such concerns have been actively used in order to generate toxic gases during film disposal and incineration. Yes.
Therefore, the present inventors have investigated the effects on agricultural products using various light quality conversion agents in agricultural films composed of polyolefin resin films in order to increase the yield of crops or improve the quality. In the light quality conversion agent, that is, the condensation product type light quality conversion agent, it was found that the yield of agricultural crops was improved and nutrients were improved, and that long-term stability of good light quality conversion ability was observed. However, on the other hand, when such a condensation product-based light quality conversion agent is contained in a normal agricultural polyethylene-based resin composition to form an agricultural film, bubbles are generated in the film, resulting in a product. As a result, a new problem has emerged.

Japanese Patent Publication No.46-24376 JP 50-88147 A Japanese Patent Laid-Open No. 06-41524 Japanese Patent Laid-Open No. 06-46684 Japanese Patent Laid-Open No. 06-46685 Japanese Patent Laid-Open No. 06-36685 JP 09-249775 A

  In view of the above problems, the object of the present invention is to contain a specific light quality conversion agent, which can increase the yield of crops and increase nutrients, and does not generate bubbles in the film. Another object of the present invention is to provide a polyethylene agricultural film capable of stably maintaining a long light quality conversion ability for a long period of time and a method for producing the same.

  As a result of intensive studies to solve the above problems, the inventors have selected an ethylene resin having a specific property as an ethylene resin constituting a layer containing a specific light quality conversion substance, An agricultural film that is homogeneous and flexible, retains strength, and has excellent light quality conversion ability is obtained. Further, a film made of the ethylene-based resin composition is formed at a temperature lower than usual, ie, 160 ° C. or lower. By forming at a temperature, it was found that bubbles were not generated in the film and a better agricultural film could be produced, and the present invention was completed.

  According to 1st invention of this application, it is an agricultural film which has at least one resin composition layer containing 0.01-5 weight part of light quality conversion agents (D) with respect to 100 weight part of polyethylene-type resin (X). The MFR (melt flow rate measured at 190 ° C., 21.18 N load) of all the polyethylene resins (X) constituting the agricultural film is 1.0 to 10 g / 10 min, and the light quality An agricultural film characterized in that the conversion agent (D) is a condensation product-based substance is provided.

  According to the second invention of the present application, in the first invention, the polyethylene resin (X) is selected from a polyethylene resin (A) obtained by an ionic polymerization method or a high-pressure radical method polyethylene resin (B). There is provided an agricultural film characterized in that it is a resin of a kind or more, and the molecular weight distribution (Mw / Mn) of the resin is 1.5 to 5.0.

  According to a third invention of the present application, there is provided an agricultural film according to the first or second invention, wherein the condensation product-based substance is a barbituric acid derivative.

According to the fourth invention of the present application, in any of the first to third inventions, the number of bubbles having an average diameter of 0.5 mm or more contained in the agricultural film is 2 or less per 1 m ^2. An agricultural film characterized in that is provided.

  According to the fifth invention of the present application, in any one of the first to fourth inventions, the agricultural film has a three-layer configuration of at least an outer layer / an intermediate layer / an inner layer, and the light quality conversion agent (D ) Is contained in the intermediate layer, an agricultural film is provided.

  Moreover, according to the sixth invention of the present application, in the fifth invention, there is provided an agricultural film characterized in that the outer layer and / or the inner layer are mainly composed of a polyethylene resin (A) by an ion polymerization method. The

  According to the seventh invention of the present application, in any of the first to sixth inventions, the MFR (melt flow rate measured under a load of 190 ° C. and 21.18 N) of the polyethylene resin (X) is 1 An agricultural film characterized by being in the range of .3 to 7.0 g / 10 min is provided.

  On the other hand, according to the eighth invention of the present application, the MFR (melt flow rate measured under a load of 190 ° C. and 21.18 N) is 1.0 to 10 g / 10 min of polyethylene resin (X) 100 parts by weight, Condensation product-based light quality conversion agent (D) is contained in an amount of 0.01 to 5 parts by weight, and the resulting resin composition is formed into a film at a molding temperature of not lower than the melting point of polyethylene resin (X) and not higher than 160 ° C A method for producing an agricultural film is provided.

  Further, according to the ninth invention of this application, the resin of all layers is obtained so that an agricultural film having a three-layer structure in which the film of the eighth invention is used as an intermediate layer and the outer layer and the inner layer are laminated on both sides thereof is obtained. There is provided a method for producing an agricultural film, wherein the composition is molded at a molding temperature of not less than the melting point of the polyethylene-based resin (X) and not more than 160 ° C.

According to the present invention, since a specific light quality conversion agent and an ethylene-based resin having a specific property that can be molded at a low temperature are combined, it is homogeneous, rich in flexibility, has strength, etc., and has excellent light quality. An agricultural film having conversion capability can be provided.
Moreover, since it shape | molds on specific temperature conditions, a bubble is not generated in a film and a more favorable agricultural film can be manufactured.

Next, the agricultural film of the present invention and the production method thereof will be described in detail.
1. [Agricultural film]
The agricultural film of this invention is an agricultural film formed by shape | molding the resin composition which contains 0.01-5 weight part of light quality conversion agents (D) with respect to 100 weight part of polyethylene-type resin (X). .

[Polyethylene resin (X)]
In the present invention, the polyethylene resin (X) means an ionic polymerization, that is, an ethylene copolymer (A) produced by an ionic catalyst and / or a low density polyethylene produced by a high pressure radical polymerization method, an ethylene copolymer. The combination (B) includes the following.

[Ethylene polymer by ion polymerization method (A)]
The ethylene polymer by the ionic polymerization method is an ethylene polymer produced by the ionic polymerization method, and is an ethylene homopolymer having a density of 0.86 to 0.97 g / cm ³ or an α having ethylene as a main component. -Copolymers with olefins are included. The density is preferably 0.86 to 0.91 g / cm ³ , an ethylene-α-olefin copolymer (hereinafter also referred to as very low density polyethylene (A1) or VLDPE), 0.91 to 0.94 g / cm ^3. And an ethylene-α-olefin copolymer (hereinafter also referred to as linear low-density polyethylene (A2) or LLDPE).

[Ultra low density polyethylene (A1)]
The ultra-low density polyethylene (A1) of the present invention has a density of 0.860 to less than 0.910 g / cm ³ , preferably a density of 0.870 to 0.905 g / cm ³ , and more preferably a density of 0.880 to 0.00. It is selected in the range of 900 g / cm ³ .
If it is this range, it will become possible to hold | maintain low temperature heat-sealing property, mechanical strength, etc., maintaining the softness | flexibility (flexibility) of a film.

[Linear low density polyethylene (A2)]
In the present invention, the linear low density polyethylene (A2) means a density of 0.910 to 0.940 g / cm ³ , preferably a density of 0.915 to 0.935 g / cm ³ , more preferably a density of 0.920 to 0. Selected in the range of 930 g / cm ³ . Within this range, mechanical strength, heat seal strength, etc. can be obtained without impairing flexibility, which is an advantage of linear low density polyethylene.

In the present invention, when the ethylene copolymer (A) obtained by the ion polymerization method is used alone as the polyethylene resin (X) as the raw material of the functional film, the melt flow rate (MFR: 190 ° C., 21.18 N load) (Measured below) is important to be selected in the range of 1 to 10 g / 10 min, and the density is preferably selected in the range of 0.860 to 0.940 g / cm ³ .

In addition, the molecular weight distribution (Mw / Mn) of the ultra-low density polyethylene (VLDPE) and the linear low density polyethylene (LLDPE) is 1.5 to 5.0, preferably 2.0 to 4.5, more preferably It is selected in the range of 2.3 to 4.0. Within this range, it is possible to provide a composition that is homogeneous and has a good balance of flexibility, transparency, mechanical strength, and the like.
If it is said range, extrusion molding, such as inflation molding and T-die molding, will be easy. In addition, Mw / Mn here is a weight average molecular weight / number average molecular weight by GPC analysis.

  Among the polyethylene resins obtained by the ion polymerization method of the present invention, the α-olefin of the ethylene-α-olefin copolymer has 3 to 12 carbon atoms, preferably 3 to 10 carbon atoms, specifically propylene, 1 -Butene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene and the like can be mentioned. The content of these α-olefins is preferably selected in the range of 3 to 40 mol%.

Ethylene polymers by ionic polymerization are manufactured using Ziegler catalysts, vanadium catalysts, Phillips catalysts, single site catalysts (including metallocene catalysts), and especially single site catalysts (including metallocene catalysts). It is desirable to be manufactured using
Examples of the ion polymerization method include a high pressure ion polymerization method, a gas phase method, a solution method, and a slurry method. In particular, an ethylene-α-olefin copolymer produced by a high pressure ion polymerization method using a metallocene catalyst is used. preferable.

The single site catalyst is not particularly limited, but preferably includes a catalyst having a metallocene compound such as a zirconium compound coordinated with a group having a cyclopentadienyl skeleton and the like, and a promoter as catalyst components. .
Commercially available ethylene-α-olefin copolymers produced with the above single-site catalyst include Harmolex (registered trademark) series, Kernel (registered trademark) series manufactured by Nippon Polyethylene, and Evolue (registered trademark) manufactured by Prime Polymer. Trademark) series, Exelen (registered trademark) GMH series manufactured by Sumitomo Chemical Co., Ltd., Excellen (registered trademark) FX series, and the like.

[High pressure radical polymerization polyethylene resin (B)]
High pressure radical polymerization polyethylene resin (B) is a low density polyethylene (B1), ethylene-vinyl ester copolymer (B2), copolymer of ethylene and an α, β-unsaturated carboxylic acid or derivative thereof. It includes at least one resin selected from the polymers (B3).

[Low-density polyethylene (B1) by high-pressure radical polymerization method] (hereinafter referred to as LDPE)
The density of the low-density polyethylene (B1) obtained by the high-pressure radical polymerization method is 0.905 to 0.940 g / cm ³ , preferably 0.910 to 0.935 g / cm ³ , and more preferably 0.912 to 0.930 g. / Cm ³ range. When the melt tension is in the range of 1.5 to 25 g, preferably 3 to 20 g, more preferably 3 to 15 g, the film moldability is good.

[Ethylene-vinyl ester copolymer (B2)]
The ethylene-vinyl ester copolymer (B2) is a copolymer produced by a high-pressure radical polymerization method and a vinyl ester monomer containing ethylene as a main component. Examples of the vinyl ester monomer include vinyl ester monomers such as vinyl propionate, vinyl acetate, vinyl caproate, vinyl caprylate, vinyl laurate, vinyl stearate, vinyl trifluoroacetate, and other copolymerization. Unsaturated monomers can be used.
Among these vinyl ester monomers, vinyl acetate is particularly preferable. That is, a copolymer comprising 50 to 99.5% by weight of ethylene, 0.5 to 50% by weight of vinyl ester, and 0 to 49.5% by weight of other copolymerizable unsaturated monomers is preferable. The vinyl ester content is 3 to 50% by weight, preferably 5 to 30% by weight.

[Copolymer of ethylene and α, β-unsaturated carboxylic acid or derivative thereof (B3)]
The copolymer of ethylene and α, β-unsaturated carboxylic acid or a derivative thereof (B3) is a copolymer of ethylene and α, β-unsaturated carboxylic acid, or a derivative thereof, and other copolymers as desired. Examples thereof include copolymers with unsaturated monomers, and metal salts (ionomers), amides, and imides thereof.
Specific examples of the α, β-unsaturated carboxylic acid that is a copolymer component include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, and itaconic acid.
Specific examples of the derivatives include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, n-butyl acrylate, and n methacrylate. -Butyl, cyclohexyl acrylate, cyclohexyl methacrylate, lauryl acrylate, lauryl methacrylate, stearyl acrylate, stearyl methacrylate, glycidyl acrylate, glycidyl methacrylate, and the like. Specific examples of these copolymers include ethylene- (meth) acrylic acid copolymers, ethylene-maleic anhydride copolymers, ethylene- (meth) acrylic acid ester copolymers, ethylene-acrylic acid-vinyl acetate. Examples thereof include binary or multi-component copolymers such as a copolymer and an ethylene-ethyl acrylate-maleic anhydride copolymer.

Other unsaturated monomers in the above are olefins having 3 to 10 carbon atoms such as propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene and 1-decene, C2 (Meth) acrylic acid esters such as vinyl esters of C3 alkanecarboxylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, glycidyl (meth) acrylate, (meth) acrylic acid , At least one selected from the group of ethylenically unsaturated carboxylic acids such as maleic acid, fumaric acid and maleic anhydride, or anhydrides thereof.
Specific examples of the above products include ethylene-methyl methacrylate copolymer (manufactured by Sumitomo Chemical Co., Ltd., ACLIFT (registered trademark) CM502), ethylene-ethyl acrylate copolymer (manufactured by Nihon Unicar, NUC (registered trademark) 6570) is commercially available.

  The ethylene copolymer is preferably a copolymer comprising 65 to 99.5% by weight of ethylene, 0.5 to 35% by weight of an unsaturated carboxylic acid or ester thereof, and 0 to 25% by weight of other unsaturated monomers. .

  In addition, when the high-pressure radical polyethylene resin (B) is used alone as the polyethylene resin (X) which is a raw material for the functional film, it is important to select it within the range of MFR 1 to 10 g / 10 min. is there.

[Other polyolefin resin (C)]
In the present invention, another polyolefin resin (C) can be mixed with the polyethylene resin of the ion polymerization method polyethylene resin (A) or the high pressure radical method polyethylene resin (B). That is, the other polyolefin resin (C) is an optional component in the present invention.
Specifically, polypropylene resins (C3 such as medium / high density polyethylene (C1), ethylene-α-olefin copolymer rubber (C2), propylene homopolymer or propylene and other α-olefin copolymers. And at least one polyolefin resin selected from the functional group-containing polyolefin resin (C4).

  In the present invention, the melt flow rate (measured under a load of MFR: 190 ° C. and 21.18 N) made of an ion polymerization polyethylene resin (A) and / or a high pressure radical polyethylene resin (B) is 1.0 to It is preferably composed of 100 to 50% by weight of a polyethylene resin (X) of 10 g / 10 minutes and 0 to 50% by weight of another polyolefin resin (C).

[Medium / High-density polyethylene (C1)]
In the present invention, the medium / high density polyethylene (C1) is a polyethylene selected in the range of density 0.94 to 0.97 g / cm ³ , preferably density 0.945 to 0.965 g / cm ³ .

[Ethylene-α-olefin copolymer rubber (C2)]
Examples of the ethylene-α-olefin copolymer rubber (C2) include copolymer rubbers of ethylene and α-olefins having 3 to 10 carbon atoms, such as ethylene-propylene copolymer rubber, ethylene-propylene-diene (EPDM). ) Copolymer rubber, ethylene-1-butene copolymer rubber and the like.
These rubber components fulfill the effect of improving the performance of the sealant film such as impact strength and pinhole resistance.
Examples of the copolymer obtained by copolymerizing a diene monomer include an ethylene / propylene / dicyclopentadiene copolymer, an ethylene / propylene / 5-ethylidene-2-norbornene copolymer, and an ethylene / propylene / 1,6-hexadiene. A copolymer etc. can be illustrated.

[Polypropylene resin (C3)]
In the present invention, the polypropylene resin is a polypropylene homopolymer such as syndiotactic polypropylene resin or isotactic polypropylene resin, a random copolymer of propylene and other α-olefin, a block copolymer, an amorphous polypropylene, or the like. Is mentioned.

[Functional group-containing polyolefin resin (C4)]
Furthermore, the functional group-containing polyolefin resin (C4) according to the present invention is a copolymer of the following functional group-containing compounds (a) (d) (e) (f) and an olefin, or a radical in the polyolefin resin. It includes a functional group-modified polyolefin resin obtained by modifying and grafting the functional group-containing compounds (a) to (f) in the presence of a generator.
The functional group-containing polyolefin resin (C4) may be a single type or a combination of two or more types.

  The functional group-containing compound of the functional group-containing polyolefin resin (C4) according to the present invention includes an epoxy group-containing compound (a), an unsaturated carboxylic acid group-containing compound or derivative thereof (b), an ester group-containing compound (c), It is at least one compound selected from the group consisting of a hydroxyl group-containing compound (d), an amino group-containing compound (e), and a silane group-containing compound (f), and an epoxy group-containing compound (a) or an unsaturated carboxylic acid An acid group-containing compound or its derivative (b) is preferred.

[Raw resin for agricultural film]
The raw film resin for the agricultural film of the present invention includes (i) an ion polymerization polyethylene resin (A), (ii) a high pressure radical polyethylene resin (B), and (iii) an ion polymerization ethylene resin (A) + Mixed resin with high pressure radical polyethylene resin (A + B), (iv) Ion polymerization polyethylene resin (A) + Other polyolefin resin (C), (v) High pressure radical polyethylene resin (B) + Other Polyolefin resin (C), (vi) ion-polymerized ethylene resin (A) + mixed resin with high-pressure radical polyethylene resin (B) + other polyolefin resin (C), (vii) (A) and / or Combinations of (B) + functional group-containing polyolefin resin (C4) and the like can be mentioned.

[Rating ratio of raw resin]
In the present invention, the polyethylene resin (X) is based on 90 to 10% by weight of the resin (A) when the ion polymerization polyethylene resin (A) and the high pressure radical polyethylene resin (B) are mixed. Resin (B) 10 to 90% by weight, preferably resin (A) 80 to 20% by weight / resin (B) 20 to 80% by weight, more preferably resin (A) 75 to 25% by weight / resin (B ) It is blended at a ratio in the range of 25 to 75% by weight.
Moreover, when mix | blending resin (C), the range of the range of 100-50 weight% / resin (C) 0-50 weight% of polyethylene-type resin (X) which consists of said resin (A) and / resin (B). Blended in proportions. Preferably, the resin (X) is 95 to 55% by weight / resin (C) 5 to 45% by weight, and more preferably the resin (X) 90 to 60% by weight / resin (C) 10 to 40% by weight is selected. It is desirable.

It is important that the polyethylene-based resin (in the case of a mixed resin, the property of the mixed resin) constituting the layer containing the light quality conversion agent of the agricultural film of the present invention satisfies the following property (a1). It is.
That is, the melt flow rate (MFR) measured under a load of (a1) 190 ° C. and 21.18 N of the polyethylene resin (X) is 1.0 to 10 g / 10 minutes, preferably 1.3 to 7.0 g / 10 minutes, more preferably 1.5 to 5.0 g / 10 minutes. If the MFR is too small, the extrusion load during low-temperature molding increases and the heat generated by the resin becomes excessive, causing a foaming phenomenon. Moreover, when MFR is too large, film-forming stability will deteriorate and we are anxious about the fall of the intensity | strength of a film.
In particular, when the agricultural film of the present invention is a laminated film, even if the layer containing the light quality conversion agent is a part of the layer, the MFR of the polyethylene resin constituting all the layers is as described above. It is characterized by a specific range.

  The molecular weight distribution (Mw / Mn) of the polyethylene resin is selected in the range of 1.5 to 5.0, preferably 2.0 to 4.5, more preferably 2.5 to 4.0. Within this range, it is possible to provide a composition that is homogeneous and has a good balance of flexibility, transparency, mechanical strength, and the like. Moreover, if it is said range, extrusion molding, such as inflation molding and T-die molding, will be easy. In addition, Mw / Mn here is a weight average molecular weight / number average molecular weight by GPC analysis.

[Light quality conversion agent (D)]
In the present invention, the light quality conversion agent (D) mainly has a property of converting wavelengths in the ultraviolet region and / or infrared region other than the visible region in sunlight into light rays that can be used for plants, for example, A light quality conversion agent having an absorption maximum at 350 to 550 nm and an emission maximum at 550 to 700 nm is preferred for agricultural applications.

The present invention is characterized by using a condensation product type light quality conversion agent among various light quality conversion agents as a light quality conversion agent, and particularly preferably a barbituric acid which is a kind of organic luminescent pigment. The use of a condensation product which is a derivative is mentioned.
Among the condensation products that are barbituric acid derivatives, in particular, a condensation product of barbituric acid and p-dimethylaminobenzaldehyde has a polyethylene resin (melt flow rate (MFR) of 1.0 to 10 g / 10 min. By using together with X) and setting the molding temperature to 160 ° C. or less, it is possible to expect a remarkable effect that a homogeneous sheet can be obtained without generation of bubbles.
Examples of the barbituric acid derivative include a condensation product of barbituric acid (d2) and p- (dialkyl) methylaminobenzaldehyde (d1) represented by the following formula.

(In the formula, R1 and R2 are independently a hydrogen atom or, for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a secondary butyl group, an isobutyl group, or a tertiary butyl group. , N-amyl group, tertiary-amyl group, hexyl group, heptyl group, octyl group, 2-ethylhexyl group, nonyl group, decyl group, dodecyl group, tetradecyl group, hexadecyl group or octadecyl group To 18 alkyl groups.)
R1 and R2 of this condensation product are preferably methyl groups.

  The condensation product is, for example, a barbituric acid derivative represented by the following formula (D1) or (D2). This condensation reaction and product (D1) are no. No. 1753-47-5 and (D2) is No. It has a CAS number of 152734-34-4. Specifically, it is a compound prepared as described in, for example, European Patent No. 1413599, and its trade name includes trade name of Ciba Specialty Chemicals Co., Ltd .: Smart Light RL1000.

  The compounding quantity of the said light quality conversion agent (D) is 0.01-5 weight part with respect to 100 weight part of polyethylene-type resin (X), Preferably it is 0.02-4 weight part, More preferably, it is 0.03. It is in the range of ~ 3 parts by weight. If the light quality conversion agent (D) is less than 0.01 parts by weight, the light quality conversion effect is not exhibited, and even if an amount of more than 5 parts by weight is added, the light quality conversion effect is not exhibited. Since the phenomenon that light quality conversion efficiency falls occurs is not preferable.

  The resin composition having the light conversion agent of the condensation product type of the present invention may be prepared by simple blending each desired composition with a Henschel mixer, an extruder, etc., such as dry blend, but preferably You may use as a masterbatch which mix | blended the light quality conversion agent in high concentration beforehand. By making a master batch in the form of pellets, handling, transportation and workability become easy, and it can be uniformly dispersed in a composition for the purpose of light quality conversion. Therefore, it is avoided that the optical properties such as the optical properties are impaired, so that the wavelength conversion efficiency of the film is remarkably improved and the long-term stability can be maintained. However, the condensation product system in the present invention, in particular the light quality conversion agent which is a barbituric acid derivative, is easily decomposed by heat and easily absorbs moisture, so that the kneading temperature at the time of blending and master batch preparation is 160 ° C. or less. It is good to make it.

2. [Laminated film]
The agricultural film of the present invention is used in a single layer configuration or a multilayer configuration. That is, the agricultural film of the present invention is a film having at least one polyethylene-based resin composition layer containing the light quality conversion agent, and can be used as a single-layer film. In the intended use, a three-layer film having a laminate structure of three or more layers and having the polyethylene resin composition layer added with the light quality conversion agent as an intermediate layer is preferable.

  When it is composed of three or more layers, in order to provide functions such as heat retention, anti-fogging, anti-fogging, and weather resistance for agricultural films, suitable resins and additives are devised in each layer. Can be used. In the present invention, the outer layer is hereinafter referred to as an outer layer during inflation molding, and the inner layer is referred to as an inner surface during house expansion. Similarly, in the present invention, the inner layer refers to an inner layer during inflation molding. It is a layer that becomes the exterior of the house when the house is extended.

For example, the inner layer (the inner layer at the time of inflation molding, the outer surface at the time of house extension is the outer surface of the house) is mainly composed of the ethylene / α-olefin copolymer that is the above-mentioned ion polymerization polyethylene resin (A) (99- 60 wt%), and a resin composition to which about 1 to 40 wt% of a low density polyethylene resin (LDPE) by a high pressure radical method is added can be used. In particular, it is preferable to use as a main component LLDPE produced with a single-site catalyst (metallocene catalyst or the like) excellent in toughness.
In addition, as described in detail above, the intermediate layer uses LLDPE of an ion polymerization polyethylene resin (A) or EVA of a low density polyethylene resin (B) by a high-pressure radical method, or a mixture of LLDPE and EVA. It is preferable to use the resin, and a remarkable effect is exhibited when the light quality conversion agent is contained.
The outer layer (the outer layer during inflation molding, the inner layer during house extension) is made of ion-polymerized polyethylene resin (A) LLDPE as the main component (99-60% by weight) as in the case of the inner layer. A resin composition to which about 1 to 40% by weight of the low density polyethylene resin (B) is added can be used.

More specifically, LL: linear low density polyethylene, VL: ultra low density polyethylene, mLL and mLL: linear low density polyethylene and ultra low density polyethylene produced using a metallocene catalyst, LD: (high pressure radical Method) When abbreviated as low density polyethylene, EVA: ethylene-vinyl acetate copolymer, examples of the multilayer film (inner layer / intermediate layer / outer layer) of the present invention include the following, In the present invention, the present invention is not limited thereto. LL / EVA + light conversion agent / LL, LL / EVA + light conversion agent / VL, LL + LD / EVA + light conversion agent / LL + LD, mLL + LD / EVA + light conversion agent / mLL + LD , MLL + LD / EVA + light conversion agent / mVL, mLL / mVL + light conversion agent / mLL, mLL + LD / mVL + light conversion agent / mLL + LD, mLL / mVL + light conversion agent / mVL, mVL / mVL + light conversion agent / EVA, mVL + LD / mVL + light conversion agent / EVA, mLL / mVL + light conversion agent / EVA, mLL + LD / mVL + light conversion agent / EVA.

The preferred laminated film of the present invention is basically composed of three layers of outer layer / intermediate layer / inner layer, and the laminated constitution ratio is such that the thickness of the outer layer is 5 to 100 μm, preferably 10 to 80 μm, more preferably 15 to 60 μm. The intermediate layer has a thickness of 10 to 150 μm, preferably 20 to 120 μm, more preferably 30 to 100 μm, and the inner layer has a thickness of 5 to 100 μm, preferably 10 to 80 μm, more preferably 15 to 60 μm. In such a three-layer laminated film, the ratio of the thickness of the outer layer, the intermediate layer and the inner layer (outer layer / intermediate layer / inner layer) is 0.2 to 4/1 to 10/1, preferably 0.5 to It is desirable that it is 2/2 to 6/1. Moreover, 30-200 micrometers is preferable, as for the thickness of the whole laminated film, More preferably, it is 50-180 micrometers, More preferably, it is the range of 70-150 micrometers.
In addition, the agricultural film of this invention can also be set as the layer structure of 4-5 layers which further provided the protective layer etc. further as needed other than three layers of an outer layer / intermediate layer / inner layer.

  The amount of the light quality conversion agent is in the range of 0.01 to 5 parts by weight, preferably 0.03 to 3 parts by weight, more preferably 0.05 to 2 parts by weight with respect to 100 parts by weight of the resin constituting the layer. It is. If the amount of the light quality conversion agent is too small, the light quality conversion effect is not exhibited, and if it is too large, a phenomenon in which the light quality conversion efficiency is deteriorated is not preferable.

[Other additives]
In the agricultural film resin composition of the present invention, various known auxiliary additives generally used in agricultural films as necessary, for example, heat retention agents, UV absorbers, antioxidants, light stabilizers, Anti-blocking agents, slip agents, heat stabilizers, neutralizing agents, anti-fogging agents, anti-fogging agents, pigments, nucleating agents, etc. are blended, or known coating-type anti-protecting agents mainly composed of inorganic sol on the outer layer surface of the film A clouding agent can be applied.

<Heat insulating agent>
As a heat retention agent used with the agricultural film of this invention, the inorganic compound which has infrared absorption ability can be used combining 1 type (s) or 2 or more types. Examples of inorganic compounds that can be used include magnesium oxide, calcium oxide, aluminum oxide, silicon oxide, lithium hydroxide, magnesium hydroxide, calcium hydroxide, aluminum hydroxide, magnesium carbonate, calcium carbonate, calcium sulfate, magnesium sulfate, Aluminum sulfate, lithium phosphate, calcium phosphate, magnesium silicate, calcium silicate, aluminum silicate, calcium aluminate, magnesium aluminate, sodium aluminosilicate, potassium aluminosilicate, calcium aluminosilicate, kaolin, clay, talc, mica, zeolite, hydrotal Sites, lithium / aluminum composite hydroxide, aluminum / lithium / magnesium composite carbonate compound, aluminum / lithium / magnesium composite silicate Things, magnesium aluminum silicon composite hydroxide, magnesium aluminum silicon composite sulfate compounds, magnesium aluminum silicon composite carbonate compound, and the like. Preferred are hydrotalcites and lithium / aluminum composite hydroxides.
The content of the heat retaining agent is preferably 1 to 20 parts by weight per 100 parts by weight of the resin.

The average particle size of the inorganic compound used as the heat retaining agent is preferably 10 μm or less, more preferably 5 μm or less, and particularly preferably 1 μm or less. An average particle size of 10 μm or less is preferable because the transparency of the film is not significantly impaired.
Insulating agents are trade names such as Mizusawa Chemical Co., Ltd., Mizukarak, Mizukarak L, Mick Ray ASi, Mick Ray FVA, Kyowa Chemical Industry Co., Ltd. DHT4A, DHT4A2, Alkamizer 1, Toda Kogyo Co., Ltd., OPTIMA LSA, etc. It is available. It is also possible to use a heat retention agent that has been treated with a surface treatment agent in advance. The heat retention agent is preferably contained in at least the intermediate layer of the laminated film.

<Ultraviolet absorber, antioxidant, hindered amine compound (light stabilizer)>
The ultraviolet absorber can be appropriately selected from known ones known as ultraviolet absorbers, and preferred examples include benzophenone ultraviolet absorbers, benzotriazole ultraviolet absorbers, and triazines. An ultraviolet absorber etc. can be mentioned.
Examples of the benzophenone ultraviolet absorber include 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-n-dodecyloxybenzophenone, 2-hydroxy-4-n-octadecyl. Oxybenzophenone, 2-hydroxy-4-benzyloxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, 2-hydroxy-5-chlorobenzophenone, 2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4 -Methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone and the like.
The benzotriazole-based ultraviolet absorber is a hydroxyphenyl-substituted benzotriazole compound, for example, 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-5-t-butylphenyl) benzo Triazole, 2- (2-hydroxy-3,5-dimethylphenyl) benzotriazole, 2- (2-methyl-4-hydroxyphenyl) benzotriazole, 2- (2-hydroxy-3-methyl-5-t-butyl) Phenyl) benzotriazole, 2- (2-hydroxy-3,5-di-t-amylphenyl) benzotriazole, 2- (2-hydroxy-3,5-di-t-butylphenyl) benzotriazole, 2- ( 2-Hydroxy-3,5-dimethylphenyl) -5-methoxybenzotriazole 2- (2-n-octadecyloxy-3,5-dimethylphenyl) -5-methylbenzotriazole, 2- (2-hydroxy-5-methoxyphenyl) -5-methylbenzotriazole, 2- (2-hydroxy- 3-t-butyl-5-methylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-5-t-butylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-5-phenylphenyl) ) -5-chlorobenzotriazole, 2- (2-hydroxy-3,5-dichlorophenylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-5-methylphenyl) -5,6-dichlorobenzotriazole, 2- (2-Hydroxy-3,5-di-t-butylphenyl) -5-chlorobenzotri Sol, 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-3-methylphenyl) -5-butoxycarbonylbenzotriazole, 2- ( 2-acetoxy-5-methylphenyl) benzotriazole, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H benzotriazole and the like. These are commercially available under trade names such as Seasorb 706, Tinuvin 328, Tinuvin P, Siasorb UV5411, and the like.
Examples of triazine ultraviolet absorbers include 2- [4,6-bis (2,4-dimethylphenyl) -1,3,5-triazin-2-yl] -5- (octyloxy) phenol, 2- ( Examples include 4,6-diphenyl-1,3,5-triazin-2-yl) -5- (hexyloxy) phenol. These are commercially available under trade names such as Siasorb UV1164 and Tinuvin 1577FF.
The ultraviolet absorber is desirably contained in a proportion of 0.01 to 5 parts by weight, preferably 0.05 to 2 parts by weight, with respect to 100 parts by weight of the resin component.

Antioxidants include hindered compounds such as butylhydroxytoluene, tetrakis [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane, octadecyldibutylhydroxyhydrocyanate, etc. Thioethers such as phenolic, diraurthiodipropionate, distearylthiodipropionate, bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite, tris (dibutylphenyl) phosphite, 4, Phosphorous antioxidants such as 4'-biphenylenediphosphinic acid tetrakis (2,4-di-t-butylphenyl) and bis (2,6-di-t-butyl-4methylphenyl) pentaerythritol diphosphite Is preferable.
The content of the antioxidant is desirably 0.01 to 5 parts by weight, preferably 0.05 to 2 parts by weight with respect to 100 parts by weight of the resin component.

Examples of hindered amine compounds (light stabilizers) include phenyl-4-piperidinyl carbonate, {4- (4-hydroxy-3,5-di-t-butylphenyl) propionyl} -N- (4-hydroxy-3 , 5-Di-t-butylphenyl) methyl-2,2,6,6-tetramethylpiperidine, 1,1 '-(1,2-ethanediyl) bis (3,3,5,5-tetramethylpiperazi Non), bis (2,2,6,6-tetramethyl-4-piperidinyl) sebacate, bis- {N-methyl-2,2,6,6-tetramethyl-piperidinyl} sebacate, bis (1,2, 2,6,6-pentamethyl-4-piperidinyl) -2- (3,5-di-t-butyl-4-hydroxybenzyl) -2-n-butylmalonate, 1,2,3,4-butanecarboxylic Acid and 2, , 6,6-Tetramethyl-4-piperidinol and tridecyl alcohol, 1,2,3,4-butanecarboxylic acid, 1,2,2,6,6-pentamethyl-4-piperidinol and triacyl Condensates with alcohols, tetrakis (2,2,6,6-tetramethyl-4-piperidinyl) -1,2,3,4-butanetetracarboxylate, tetrakis (1,2,2,6,6-pentamethyl -4-piperidinyl) -1,2,3,4-butanetetracarboxylate, poly {[6- (1,1,3,3-tetramethylbutyl) amino-1,3,5-triazine-2,4 -Diyl] [(2,2,6,6-tetramethylpiperidinyl) imino] hexamethylene [(2,2,6,6-tetramethylpiperidinyl) imino]}, poly {6-morpholino- -Triazine-2,4-diyl [(2,2,6,6-tetramethylpiperidyl) imino-hexamethylene] [(2,2,6,6-tetramethylpiperidinyl) imino]}, 1,2 , 3,4-Butanetetracarboxylic acid, 2,2,6,6-tetramethyl-4-piperidinol and β, β, β ′, β′-tetramethyl-3,9- (2,4,8,10 -Condensation with tetraoxaspiro [5.5] undecane) diethanol, N, N'-bis (3-aminopropyl) ethylenediamine 2,4-bis [N-butyl-N (1,2,2,6, 6-pentamethyl-4-piperidyl) amino] -chloro-1,3,5-triazine condensate, polyester of 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol and succinic acid, 1 , 2,3,4-pigs Tetracarboxylic acid, 1,2,2,6,6-pentamethyl-4-piperidinol and β, β, β ′, β′-tetramethyl-3,9 (2,4,8,10-tetraoxaspiro [5 .5] undecane) condensates with diethanol, trimethylpropyl-3-oxy- [4 (2,2,6,6-tetramethyl) piperidinyl] siloxane and the like, among which 4-hydroxy-2 is the most preferred one , 2,6,6-tetramethyl-1-piperidineethanol and a succinic acid condensate.
The hindered amine compound may be blended in an amount of 0.05 to 2 parts by weight with respect to 100 parts by weight of the resin component.

<Anti-fogging agent>
The anti-fogging agent prevents the generation of pests caused by a decrease in irradiation sunlight due to a decrease in transparency caused by water droplets adhering to the film surface and a drop of the attached water droplets. Examples of the compound used for the antifogging agent include glycerin monostearate, glycerin monobeherate, sorbitan monostearate, sorbitan monobeherate, sorbitan monopalmitate, sorbitan palmitate (ethylene oxide adduct) and the like. These may be used alone or in combination.
The amount of the antifogging agent varies depending on the thickness of the film, but is generally in the range of 0.3 to 3.0 parts by weight. The antifogging agent is preferably contained in at least the outer layer of the laminated film (the inner surface side during house extension) and the intermediate layer.

3. [Manufacture of agricultural film]
The agricultural laminated film of the present invention can be produced by molding a resin composition containing a predetermined additive by a known molding method. The manufacturing method is not particularly limited. For example, an air-cooled blown film is formed by a laminated die having an extruder and a normal feed block type, a multi-manifold type, and a multi-slot type joining / merging portion according to the number of laminated layers. Examples include T-die film molding, and a suitable film can be obtained by any of these methods, but inflation film molding is particularly preferable.

Conventionally, when an agricultural film is produced by an inflation molding method or the like, it is generally molded at a temperature of about 180 to 210 ° C. However, in the method for producing an agricultural film of the present invention, the above polyethylene is used. The molding temperature of the layer composed of the polyethylene resin composition composed of the resin based resin (X) and the light quality conversion agent (D) can be molded by adopting a temperature range that is not lower than the melting point of the polyethylene based resin and not higher than 160 ° C. It is essential. The agricultural film is preferably molded in the range of 155 ° C. or less, more preferably 150 ° C. or less as the upper limit temperature, and preferably in the range of 140 ° C. or more, more preferably 145 ° C. or more as the lower limit temperature.
More preferably, the molding temperature of not only the layer containing the light quality conversion agent but also all the layers of the laminated film composed of three or more layers is in the above range. When the molding temperature is within this range, it is possible to provide an agricultural film that is homogeneous and flexible without bubbles and has excellent mechanical strength such as piercing strength.

  In the present invention, a condensation product-based substance, particularly a condensation product of barbituric acid and p-dimethylaminobenzaldehyde is contained as a light quality conversion agent. For this reason, bubbles are likely to form at the normal polyolefin film forming temperature, especially at relatively medium and high temperatures where the molding temperature is 160 ° C. or higher, but in the present invention, a specific resin that can be molded at a low temperature of 160 ° C. or lower is selected. Therefore, occurrence of such a problem at the time of molding can be prevented.

The agricultural film produced under the above conditions desirably has 2 or less, preferably 1 or less bubbles per 1 m ² in the film with an average diameter of 0.5 mm or more. By using a film with few bubbles, the performance is further improved.

  The thickness of the agricultural film of the present invention is not particularly limited, but is preferably selected in the range of 20 μm to 300 μm. If the thickness is 20 μm or less, it is too thin, the workability during molding deteriorates, and the mechanical strength decreases, which is not preferable. Moreover, what exceeds 300 micrometers becomes a thing with bad handleability.

  In the present invention, it is also preferable to roughen one of the outermost layers of the laminated film and use the processed surface toward the plant cultivation side of the house. That is, the light emission in the light quality conversion agent-containing layer varies depending on the refractive index of the resin, but the emitted light is totally reflected at the interface with air and propagates through the film, and the confined light repeats absorption light emission. In order to effectively radiate (irradiate) the light emitted at this time to the cultivated plant from the inner surface of the film, it is preferable to perform a roughening process by providing irregularities on the inner surface of the film. The roughening process can be performed by a commonly practiced method such as a wire brush, sandblasting, embossing, or the like.

  Examples of the present invention will be specifically described below, but the present invention is not limited to these examples. In addition, the physical-property measuring method and raw material which were used by each Example and the comparative example are as follows.

1. Evaluation Method of Resin Physical Properties (1) Melt Flow Rate (MFR): MFR of polyethylene resin was measured according to JIS-K6922-2: 1997 appendix (190 ° C., 21.18 N load).
(2) Density: Measured according to JIS K-7112.
(3) Mw / Mn: Measured by GPC shown below.
Apparatus: Waters GPC 150C type Detector: MIRAN 1A infrared spectrophotometer (measurement wavelength, 3.42 μm)
Column: Showa Denko Co., Ltd. AD806M / S 3 (column calibration is Tosoh monodisperse polystyrene (A500, A2500, F1, F2, F4, F10, F20, F40, F288 each 0.5 mg / ml solution) The logarithm of the elution volume and molecular weight was approximated by a quadratic equation, and the molecular weight of the sample was converted to polyethylene using the viscosity equation of polystyrene and polyethylene, where the coefficient of the viscosity equation of polystyrene was α = 0. .723, log K = −3.967, and polyethylene has α = 0.723 and log K = −3.407.)
Measurement temperature: 140 ° C
Injection volume: 0.2ml
Concentration: 20 mg / 10 mL
Solvent: Orthodichlorobenzene Flow rate: 1.0 ml / min

2. Raw materials (1) Ion polymerization polyethylene (A)
Ethylene / α-olefin copolymer (A1): manufactured by Nippon Polyethylene Co., Ltd., kernel KF282 (MFR 2.2 g / 10 min, density 0.915 g / cm ³ , Mw / Mn: 2.59)
Ethylene / α-olefin copolymer (A2): manufactured by Nippon Polyethylene Co., Ltd., Harmolex NF444A (MFR 2.0 g / 10 min, density 0.912 g / cm ³ , Mw / Mn: 2.88)
Ethylene / α-olefin copolymer (A3): manufactured by Nippon Polyethylene Co., Ltd., Harmolex NF324A (MFR 1.0 g / 10 min, density 0.906 g / cm ³ , Mw / Mn: 3.01
Ethylene / α-olefin copolymer (A4): manufactured by Nippon Polyethylene Co., Ltd., Novatec LL UH410 (MFR 0.45 g / 10 min, density 0.923 g / cm ³ , Mw / Mn: 3.50
(2) High pressure radical polyethylene (B)
High-pressure radical polyethylene (B1): manufactured by Nippon Polyethylene Co., Ltd., Novatec EVA LV440 (MFR 2.0 g / 10 min, vinyl acetate content 15 wt%, Mw / Mn: 4.39)
High-pressure radical polyethylene (B2): manufactured by Nippon Polyethylene Co., Ltd., Novatec EVA LV211 (MFR 0.3 g / 10 min, vinyl acetate content 6.3 wt%, Mw / Mn: 4.95
High-pressure radical polyethylene (B3): manufactured by Nippon Polyethylene Co., Ltd., Novatec EVA LV372 (MFR 12 g / 10 min, vinyl acetate content 15 wt%, Mw / Mn: 4.2
High-pressure radical polyethylene (B4): manufactured by Nippon Polyethylene Co., Ltd., Novatec LD LF405M (MFR 2.0 g / 10 min, density 0.920, Mw / Mn: 8.0)
High-pressure radical polyethylene (B5): manufactured by Nippon Polyethylene Co., Ltd., Novatec LD LFLF440B (MFR 2.8 g / 10 min, density 0.924, Mw / Mn: 4.43
(3) Light quality conversion substance (D)
Condensation product of barbituric acid and p-dimethylaminobenzaldehyde Ciba Specialty Chemicals Co., Ltd., SMARTLIGHT RL1000

3. Evaluation Method of Film (1) Evaluation of Foaming Property (Bubble) Ten samples of 1 m ² were randomly collected from a film having a thickness of 100 μm formed by an inflation film forming method. Thereafter, bubbles with a size of 0.5 mm or more in the collected film were visually counted, and the average value of 10 sheets was evaluated as the number of bubbles generated. The smaller the number of bubbles generated, the better the film, and the larger the number of bubbles, the less preferable the film.

(2) Evaluation of fluorescence characteristics (light quality conversion) The reflectance of a film having a thickness of 100 μm formed by the inflation film forming method was measured with a spectrocolorimeter manufactured by Konica Minolta: CM-2600d. Good when the reflectance of 620 nm to 680 nm when a white plate is measured on the opposite side of the film and the light source is 120% or more when the reflectance when no light quality conversion substance is added is 100% It was marked as “Good” because it was undergoing light quality conversion. Since the reflectance lower than 120% is not suitable as a light quality conversion film, it was set as x.

(3) Punching impact strength The punching impact strength is in accordance with JIS-P8134 (1976). The pendulum has a 90 ° arc-shaped arm to which a penetrating part can be attached at the tip and can vibrate freely. The standard is made of 12.7mmφ spherical metal, the surface has a specular gloss and can be securely attached to the tip of the arcuate arm of the pendulum, and the test is equipped with a clamp with an inner diameter of 50mmφ that clamps the test piece horizontally and uniformly. The penetration fracture energy was measured using a machine.

(4) Molding stability The fold diameter variation of the film during the inflation film molding was measured, and the molding stability was evaluated according to the following criteria.
Folding diameter fluctuation is within the range of +5 mm to -0 mm of the predetermined folding width; ○ When folding diameter fluctuation deviates from the above range: ×

(5) Nutritional value of cultivated vegetables A 100 μm thick film formed by an inflation film forming method was spread on a tunnel material, and Komatsuna was cultivated therein. The seeds were harvested on day 85 and measured for total ascorbic acid content. The ratio when the total ascorbic acid content when the light quality conversion agent was not added was set to 1 was confirmed.
If this ratio is greater than 1, it is possible that the light conversion film has amplified the wavelength effective for the production of total ascorbic acid in Komatsuna, suggesting that it is effective in producing highly nutritious crops. . If the ratio is less than 1, the light conversion film may have inhibited the wavelength effective for the production of total ascorbic acid of Komatsuna, and may reduce the nutritional value of the cultivated crop.
The total ascorbic acid content was quantified by HPLC using a high performance liquid chromatograph 10A manufactured by SHIMADZU.

Example 1
First, as an agricultural film raw material resin composition comprising three layers of outer layer / intermediate layer / inner layer, 100 parts by weight of ethylene / α-olefin copolymer (A1) is used in the outer layer part, and erucic acid amide is used as the lubricant in an amount of 0.001. 1 part by weight, premixed with 0.2 part by weight of silica as an anti-blocking agent, 100 parts by weight of high-pressure radical polyethylene (B1) as an intermediate layer, and Ciba Japan Co., Ltd. as a light quality conversion agent 1 part by weight of SMARTLIGHT RL1000 and 8 parts by weight of DHT4A manufactured by Kyowa Chemical Co., Ltd. as a heat retention agent, and 100 parts by weight of an ethylene / α-olefin copolymer (A1) as a slip agent in the inner layer part It was prepared by premixing 0.15 parts by weight of erucic acid amide and 0.25 parts by weight of silica as an antiblocking agent.
Next, using a Tommy machine industry 3 type 3 layer blown film molding machine (die diameter 100 mmφ), blown film is formed at a forming temperature of 150 ° C., the outer layer thickness is 20 μ, the intermediate layer thickness is 60 μ, the inner layer A three-layer film having a thickness of 20 μm was obtained.
The outer layer of the obtained film was coated with a brush roll coater using “ZMYPK12” manufactured by Nippon Polyethylene Co., Ltd. and dried to form an antifogging film of silica sol 0.5 g / m ^{2 on} the film surface. The evaluation results of the obtained film are shown in Table 1.

(Example 2)
Example except that 80 parts by weight of ethylene / α-olefin copolymer (A1) and 20 parts by weight of high-pressure radical polyethylene (B5) were used as the base resin for the outer layer part and inner layer part. Table 1 shows the evaluation results of the film obtained by blending, forming, and coating in the same manner as in No. 1 to obtain a three-layer film having an outer layer thickness of 20 μm, an intermediate layer thickness of 60 μm, and an inner layer thickness of 20 μm. .

(Example 3)
100 parts by weight of ethylene / α-olefin copolymer (A2) is used as the base resin for the outer layer and inner layer, and 100 parts by weight of ethylene / α-olefin copolymer (A3) is used as the base resin for the intermediate layer. In the same manner as in Example 1, blending, molding, and coating were performed, and a three-layer film having an outer layer thickness of 20 μm, an intermediate layer thickness of 60 μm, and an inner layer thickness of 20 μm was obtained. Evaluation of the obtained film The results are shown in Table 1.

(Comparative Example 1)
Except for the base resin of the intermediate layer portion being 100 parts by weight of the high-pressure radical polyethylene (B2), blending, molding and coating were performed in the same manner as in Example 1, the outer layer thickness was 20 μ, the intermediate layer thickness was 60 μ Table 1 shows the evaluation results of the obtained film obtained as a three-layer film having a thickness of 20 μm.

(Comparative Example 2)
Except for the base resin of the intermediate layer part being 100 parts by weight of high-pressure radical polyethylene (B3), blending, molding and coating were carried out in the same manner as in Example 1, the outer layer thickness being 20 μm, the intermediate layer thickness being 60 μm, the inner layer being Table 1 shows the evaluation results of the obtained film obtained as a three-layer film having a thickness of 20 μm.

(Comparative Example 3)
The outer layer part and the inner layer part were blended, molded, and coated in the same manner as in Example 1 except that the base resin of the ethylene / α-olefin copolymer (A4) was 100 parts by weight. Table 1 shows the evaluation results of the obtained film obtained by obtaining a three-layer film having a thickness of 60 μm and an inner layer thickness of 20 μm.

(Comparative Example 4)
Except for adding 7 parts by weight of the light quality conversion agent SMARTLIGHT RL1000 in the intermediate layer part, blending, molding and coating were performed in the same manner as in Example 1, and the outer layer thickness was 20μ, the intermediate layer thickness was 60μ, Table 1 shows the evaluation results of the obtained film obtained as a three-layer film having a thickness of 20 μm.

(Comparative Example 5)
Except for not including the light quality conversion agent SMARTLIGHT RL1000 in the intermediate layer part (addition amount was set to 0 part by weight), blending, molding and application were performed in the same manner as in Example 1, and the thickness of the outer layer was 20 μm, and the thickness of the intermediate layer Table 1 shows the evaluation results of the film obtained by obtaining a three-layer film having a thickness of 60 μm and an inner layer thickness of 20 μm.

(Comparative Example 6)
Except for setting the inflation film forming temperature to 180 ° C., blending, molding and coating were carried out in the same manner as in Example 1 to obtain a three-layer film having an outer layer thickness of 20 μm, an intermediate layer thickness of 60 μm, and an inner layer thickness of 20 μm. Table 1 shows the evaluation results of the obtained film.

(Evaluation results)
From the result of Table 1, Examples 1-3 mix | blend the predetermined amount of light quality conversion agents with resin of the specific MFR range, and there is no bubble by shape | molding all at a molding temperature of 160 degrees C or less. An agricultural film having a uniform fluorescence property (light quality conversion ability) was obtained.
On the other hand, in Comparative Examples 1 and 2, since the MFR of the polyethylene resin used for the intermediate layer was outside the range of the present invention, there were many bubbles or the film formation stability was poor. Further, in Comparative Example 3, the MFR of the polyethylene resin used for the inner layer and the outer layer was outside the range of the present invention, so that there were many bubbles.
Moreover, Comparative Examples 4-6 did not contain a light quality conversion substance, or the compounding quantity was outside the range of this invention, and the effect was not exhibited. In particular, in Comparative Example 4, the blending amount of the light quality conversion agent was excessive at 7 parts by weight, and the fluorescence characteristics (light quality conversion ability) were rather lowered.

  The agricultural film of the present invention uses a resin composition in which a specific amount of a light quality conversion agent is blended with a polyethylene-based resin (X) having specific properties, so that there is no generation of air bubbles during molding, and flexibility. It is useful as an agricultural house sheet because of its excellent light quality conversion ability.

Claims (9)

  An agricultural film having at least one resin composition layer containing 0.01 to 5 parts by weight of a light quality conversion agent (D) with respect to 100 parts by weight of a polyethylene resin (X), which constitutes an agricultural film All polyethylene-based resins (X) have a MFR (melt flow rate measured at 190 ° C. under a load of 21.18 N) of 1.0 to 10 g / 10 minutes, and the light quality conversion agent (D) is condensed. An agricultural film characterized by being a physical substance.   The polyethylene resin (X) is at least one resin selected from an ion polymerization polyethylene resin (A) or a high pressure radical polyethylene resin (B), and the molecular weight distribution (Mw / Mn) of the resin ) Is from 1.5 to 5.0, the agricultural film according to claim 1.   The agricultural film according to claim 1 or 2, wherein the condensation product-based substance is a barbituric acid derivative. 4. The agricultural film according to claim 1, wherein the number of air bubbles having an average diameter of 0.5 mm or more contained in the agricultural film is 2 or less per 1 m ^2. .   The agricultural film has a three-layer configuration of at least an outer layer / an intermediate layer / an inner layer, and the light quality conversion agent (D) is contained in the intermediate layer. Agricultural film according to 1.   The agricultural film according to claim 5, wherein the outer layer and / or the inner layer contains a polyethylene resin (A) by an ion polymerization method as a main component.   The MFR (melt flow rate measured under a load of 190 ° C. and 21.18 N) of the polyethylene resin (X) is within a range of 1.3 to 7.0 g / 10 minutes. The agricultural film according to any one of 6.   Condensation product type light quality conversion agent (D) with respect to 100 parts by weight of polyethylene resin (X) having an MFR (melt flow rate measured at 190 ° C. under a load of 21.18 N) of 1.0 to 10 g / 10 min. ) In an amount of 0.01 to 5 parts by weight, and the obtained resin composition is molded at a molding temperature of not lower than the melting point of the polyethylene resin (X) and not higher than 160 ° C. Production method.   The resin composition of all layers is a melting point of the polyethylene resin (X) so that an agricultural film having a three-layer structure in which the film according to claim 8 is used as an intermediate layer and an outer layer and an inner layer are laminated on both sides thereof is obtained. Above, the manufacturing method of the agricultural film characterized by shape | molding at the shaping | molding temperature used as 160 degrees C or less.